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Based on some results on reparmetrisation of time in Hamiltonian path integral formalism, a pseudo time formulation of operator formalism of quantum mechanics is presented. Relation of reparametrisation of time in quantum with super…

High Energy Physics - Theory · Physics 2016-04-21 A. K. Kapoor

A new approach to normal operators in real Hilbert spaces is discussed, and a spectral representation is obtained, derived directly from the complex case. The results are then applied to quaternionic normal operators, regarded as a special…

Functional Analysis · Mathematics 2025-07-28 Florian-Horia Vasilescu

We introduce an alternative way to understand the decomposition of a quantum system into interacting parts and show that it is natural in several physical models. This enables us to define a reduced density operator for a working system…

Quantum Physics · Physics 2022-09-08 Adam Stokes

Nonlinear dynamical systems are ubiquitous in science and engineering, yet analysis and prediction of these systems remains a challenge. Koopman operator theory circumvents some of these issues by considering the dynamics in the space of…

Numerical Analysis · Mathematics 2020-02-17 Mason Kamb , Eurika Kaiser , Steven L. Brunton , J. Nathan Kutz

Even linear operators on infinite-dimensional spaces can display interesting dynamical properties and yield important links among functional analysis, differential and global geometry and dynamical systems, with a wide range of…

Functional Analysis · Mathematics 2012-11-20 C. T. J. Dodson

We discuss two distinct aspects in supersymmetric quantum mechanics. First, we introduce a new class of operators A and $\bar{A}$ in terms of anticommutators between the momentum operator and N+1 arbitrary superpotentials. We show that…

High Energy Physics - Theory · Physics 2013-07-04 E. A. Gallegos , A. J. da Silva , D. Spehler

We reconstruct quantum mechanics by introducing "information operators" and excluding the concept of wave functions. Multiple information operators simultaneously describe a single system and continuously develop in time even in the process…

Quantum Physics · Physics 2008-08-23 Ken'ichi Takano

In this letter we show that the field of Operator Space Theory provides a general and powerful mathematical framework for arbitrary Bell inequalities, in particular regarding the scaling of their violation within quantum mechanics. We…

Quantum Physics · Physics 2014-11-20 M. Junge , C. Palazuelos , D. Perez-Garcia , I. Villanueva , M. M. Wolf

We suggest a physical interpretation of the Uhlmann amplitude of a density operator. Given this interpretation we propose an operational approach to obtain the Uhlmann condition for parallelity. This allows us to realize parallel transport…

Quantum Physics · Physics 2007-05-23 Johan Aberg , David Kult , Erik Sjöqvist , D. K. L. Oi

Quantum Information is a new area of research which has been growing rapidly since last decade. This topic is very close to potential applications to the so called Quantum Computer. In our point of view it makes sense to develop a more…

Quantum Physics · Physics 2011-08-23 A. Baraviera , C. F. Lardizabal , A. O. Lopes , M. Terra Cunha

We consider some basic problems associated with quantum mechanics of systems having a time-dependent Hilbert space. We provide a consistent treatment of these systems and address the possibility of describing them in terms of a…

Quantum Physics · Physics 2024-09-24 Ali Mostafazadeh

We propose a generalization of Heisenberg picture quantum mechanics in which a Lagrangian and Hamiltonian dynamics is formulated directly for dynamical systems on a manifold with non--commuting coordinates, which act as operators on an…

High Energy Physics - Theory · Physics 2010-11-01 Stephen L. Adler

Different quantum mechanical operators can correspond to the same classical quantity. Hermitian operators differing only by operator ordering of the canonical coordinates and momenta at one moment of time are the most familiar example.…

Quantum Physics · Physics 2009-11-11 August W. Bosse , James B. Hartle

The original intent of the Koopman-von Neumann formalism was to put classical and quantum mechanics on the same footing by introducing an operator formalism into classical mechanics. Here we pursue their path the opposite way and examine…

Quantum Physics · Physics 2023-03-08 Igor Mezic

By taking a Poisson limit for a sequence of rare quantum objects, I derive simple formulas for the Uhlmann fidelity, the quantum Chernoff quantity, the relative entropy, and the Helstrom information. I also present analogous formulas in…

Quantum Physics · Physics 2021-08-20 Mankei Tsang

Metrics and pseudometrics are defined on the group of unitary operators in a Hilbert space. Several explicit formulas are derived. A special feature of the work is investigation of pseudometrics in unitary groups. The rich classes of…

Quantum Physics · Physics 2019-09-26 Manas K Patra

In infinite-dimensional Hilbert spaces, the application of the concept of quasi-Hermiticity to the description of non-Hermitian Hamiltonians with real spectra may lead to problems related to the definition of the metric operator. We discuss…

Quantum Physics · Physics 2009-11-10 R. Kretschmer , L. Szymanowski

Transformer architectures are typically described in algorithmic and statistical terms, leaving their internal mechanics without a familiar structural language for researchers trained in physical theories. To bridge this gap, we develop a…

Disordered Systems and Neural Networks · Physics 2026-03-18 Po-Hao Chang

We consider quantum dynamics for which the strict adiabatic approximation fails but which do not escape too far from the adiabatic limit. To treat these systems we introduce a generalisation of the time dependent wave operator theory which…

Quantum Physics · Physics 2015-06-16 David Viennot

We provide a method to write down the density operator for any pure state of multi-qubit systems in the multiparticle spacetime algebra (MSTA) introduced by Doran, Gull, and Lasenby. Using the MSTA formulation, we analyze several aspects of…

Quantum Physics · Physics 2018-04-24 Chih-Wei Wang